Question 736:

• JAMB 1993

A beam of light is incident from air to water at an angle of 30^oC. Find the angle of refraction if the refractive index of water is \(\frac{4}{3}\)

A. 15^oC
B. 18^oC
C. 22^oC
D. 24^oC

Question 737:

• JAMB 1993

The property of the eye known as its power of accommodation is controlled by the

A. Pupil
B. Virteous humour
C. Iris
D. Ciliary muscles

Question 738:

• JAMB 1993

Which of the following correctly explain(s) why a green leaf appears green in bright day light? i. it absorbs only the green component of sunlight. ii. it absorbs all colour of sunlight except green. iii. it reflects only the green component of sunlight.

A. I only
B. Ii only
C. I and iii only
D. Ii and iii only

Question 739:

• JAMB 1993

Which of the following correctly explains why soft iron is proffered to steel in electromagnets? i. soft iron is more readily magnetized than steel. ii. soft iron is more readily demagnetized than steel. iii. soft iron retains magnetism more than steel.

A. I only
B. Ii and iii only
C. I and ii only
D. I, ii, and iii.

Question 740:

• JAMB 1993

A current carrying conductor experiences a force when placed in a magnetic field because the

A. Conductor is magnetized
B. Magnetic field of the current interacts with external magnetic field
C. Force is due to the motor principle
D. Electric field of the current interacts with the external magnetic field